This invention relates to a manifold protection apparatus and, more particularly, to apparatus for protecting a manifold associated with a gas turbine engine from the deleterious effects of particles entrained in the gas flow stream of the gas turbine engine.
Gas turbine engines of modern vintage utilize lightweight materials, such as titanium, as structural members in the construction of various components of the fan and compressor section of the engine. For instance, compressor rotors, rotor and stator airfoils, compressor casings and frames have all been constructed of titanium materials. These components have generally exhibited excellent performance and life characteristics during prolonged operation in the severe environment encountered in a gas turbine engine.
On extremely rare occasions, during the course of engine operation, abnormal conditions, such as fan blade, turbine blade or bearing failure may cause high unbalance of the rotating components of the engine. In such instances, rotating compressor blades may rub against their respective stationary casings whereupon friction-generated heat and high internal pressure of the engine may cause titanium particles to ignite and burn. Molten, burning titanium particles may enter the high velocity gas flow stream for passage downstream.
Associated with the compressor section of a gas turbine engine, bleed manifolds are disposed at selected locations along the axial length of the compressor for the purpose of drawing off pressurized air required for turbine cooling and for various mechanical systems on board the aircraft. The manifolds are generally constructed of relatively thin and unprotected walls which are particularly susceptible to the deleterious effects of the aforementioned molten burning titanium particles. More particularly, high velocity pressurized air, in which the titanium particles are entrained, passes through bleed apertures in the compressor casing into the manifold where the molten, burning particles impinge upon the aforementioned thin manifold walls. While the burn life of the titanium particles is limited to a short period of time, a few seconds in most instances, the intense momentary local incendiary action of the titanium particles may cause damage to the thin manifold walls. The present invention is directed toward protecting the manifold walls from the deleterious effects of the incendiary titanium particles.
Therefore, it is an object of the present invention to provide apparatus for protecting a manifold associated with a gas turbine engine from the deleterious effects of particles entrained in the gas stream of the gas turbine engine.